The invention relates to a mounting assembly for mounting a spray head, especially one used in fire fighting, to an opening in a wall. More specifically, the invention relates to a mounting assembly for mounting a spray head to walls of different thicknesses, according to the preambles of the accompanying claims. The wall may be vertical, horizontal or at any angle. Herein, the term ‘wall’ thus also refers to ceilings, for instance.
The invention also relates to combinations of a spray head and a spray head mounting assembly, according to the preambles of the accompanying claims.
Spray heads used in fire fighting are mounted on different bases and fastening points depending on the application. The present invention relates to mounting spray heads to walls, which is the usual way of mounting spray heads. The walls are typically either horizontal or vertical.
International patent application No. WO 99/34872 discloses mounting assembly for mounting a spray head to an opening in a wall. The mounting assembly comprises a holder which is fastened by screws to the wall and has threads for receiving the spray head. When the holder is screwed to the wall, its angle of rotation to the opening in the wall cannot be changed without loosening the screws and fastening them to another point of the wall. Such mounting assembly is difficult to install, especially if the spray head to be fastened to the holder is asymmetric, i.e. directional, which will be discussed in the following.
Mounting spray heads to thick walls in particular is time-consuming and difficult especially when a firm and stylish mounting is required. It is especially difficult to mount a spray head to an opening extending through a thick concrete wall so that the supply line of the spray head is behind the wall. As known, the spray head can be bolted (or screwed) to the wall, in which case the spray head comprises a flange having holes on the rim, through which bolts (screws) are drawn into the concrete wall. This is a difficult mounting method, because it requires drilling holes in the concrete wall and using inserts, or the like, to which the bolts (screws) tighten. Concrete tends to crack when holes are drilled into it, because the holes must, in practice, be located very close to the opening in the wall.
Spray heads are sometimes designed to spray asymmetrically to the side(s). The spray pattern can be inclined to the side or inclined downwards, or asymmetric in another manner according to the requirements of the mounting location. These asymmetric, i.e. directional, spray heads must be mounted at a certain angle (of rotation) in relation to the opening in the wall to achieve the required spray direction.
As known, directional spray heads are mounted to the supply line by means of an elastic hose or pipe. By flexing the hose and pipe allow the spray head to be turned enough so as to mount the spray head at a desired angle, after which the spray head is fastened with bolts, or the like, to the wall. The fastening to the wall is necessary, because a pipe or especially a hose does not function as a sufficiently firm support to the spray head. If the operating pressure of the spray head is very high, for instance over 50 bar, the fastening must be especially firm.
As known, a directional spray head can be fastened to a rigid supply pipe by means of a rotatable sleeve with a PTFE tape (Teflon tape) installed between the threads of the sleeve and the supply pipe. The PTFE tape allows the spray head to be fastened to the supply pipe relatively rigidly in the desired angle so that rotation of the spray head is unlikely to occur, and the tape also acts as a sealing. Mounting the spray head in such a way only on the supply pipe does not, however, provide a sufficiently rigid fastening for all applications, especially if the spray head shall be able to work with a high operating pressure. In such conditions, the spray head must additionally be fastened to the wall e.g. with bolts (as mentioned above).
When a spray head, typically a sprinkler, i.e. a spray head with a heat-explosive glass ampoule or another means which breaks or melts in high temperatures, fastened to a wall using the known methods is triggered due to a fire, it must be removed after use and replaced with a new one. If the spray head being replaced is of the directional type, a new spray head typically does not settle at the same angle of rotation so that its nozzles spray into the same direction as those of the earlier spray head. This is because the starting point of the threads of individual spray heads varies due to manufacturing reasons. Because of this, difficult special action must be taken in mounting a new directional spray head, such as bending of hoses/pipes and/or drilling new holes in the wall and installing new inserts, so as to achieve the correct angle for the nozzle(s) of the spray head.